In the Nordic countries (Denmark, Finland, Norway, and Sweden), it is generally accepted that girls are better readers than boys, which is borne out by a lot of testing. Tests administered to students at the ages of 10, 15, and 16-24 bear this out, with the gap starting around 10, widening a great deal by 15, and then closing by age 16 to 24. What this seems to show is that girls are better readers when younger, but by adulthood, both sexes are reading at pretty much the same level.

Researchers from the University of Stavanger in Norway decided to investigate this phenomenon, which has been tested previously. They decided to look at the tests themselves, however, and see if they were designed in ways that favored girls at those ages. That seems to be the explanation.

“Based on earlier research, it appears that … the tests used in schools are designed it a way that may favor girls,” said researcher Judith Solheim. “[The test used to determine adult literacy] is designed differently. This could be one explanation as to why we are seeing gender differences in the results.”

The differences in the tests are subtle, though. The tests used in schools tend to feature long passages of text, including fiction, and it turns out that girls are better at reading continuous passages and fictional narratives. The tests given to older readers used only factual text and were evenly split between shorter text and more visual pieces, like graphs. Younger girls are also, generally, more eager to please and more motivated to do well on a test that didn’t matter to their grades, while boys tend to question the value of such tests earlier in life. Girls also tended to work harder on long-form questions that required written answers, while boys skip those more often. The adult literacy test is comprised of multiple-choice questions rather than essay questions.

The researchers are concerned that, by building tests that inadvertently favor girls over boys, these tests may be producing bad or incomplete data, which seems like a fair argument. The goal then, must be to develop tests that fairly test students of all sexes, and to avoid swinging in the opposite direction.

The researchers have also questioned whether the tests for older students are making it seem like boys have higher reading comprehension than they really do.

“This means that the challenge now is to find out how we can create reading tests that accurately demonstrate the actual skills of all boys and girls, and men and women, in terms of reading. That would give us a better basis for saying whether there really is reason to be concerned about boys’ reading skills,” Solheim said.